jQuery.autocomplete = function(input, options) {
	// Create a link to self
	var me = this;
	// Create jQuery object for input element
	var $input = $(input).attr("autocomplete", "off");
	// Apply inputClass if necessary
	if (options.inputClass)
		$input.addClass(options.inputClass);
	// Create results
	var results = document.createElement("div");
	// Create jQuery object for results
	var $results = $(results);
	$results.hide().addClass(options.resultsClass).css("position", "absolute");
	if (options.width > 0)
		$results.css("width", options.width);
	// Add to body element
	$("body").append(results);
	input.autocompleter = me;
	var timeout = null;
	var prev = "";
	var active = -1;
	var cache = {};
	var keyb = false;
	var hasFocus = false;
	var lastKeyPressCode = null;
	// flush cache
	function flushCache() {
		cache = {};
		cache.data = {};
		cache.length = 0;
	};
	// flush cache
	flushCache();
	// if there is a data array supplied
	if (options.data != null) {
		var sFirstChar = "", stMatchSets = {}, row = [];
		// no url was specified, we need to adjust the cache length to make sure
		// it fits the local data store
		if (typeof options.url != "string")
			options.cacheLength = 1;
		// loop through the array and create a lookup structure
		for (var i = 0; i < options.data.length; i++) {
			// if row is a string, make an array otherwise just reference the
			// array
			row = ((typeof options.data[i] == "string")
					? [options.data[i]]
					: options.data[i]);
			// if the length is zero, don't add to list
			if (row[0].length > 0) {
				// get the first character
				sFirstChar = row[0].substring(0, 1).toLowerCase();
				// if no lookup array for this character exists, look it up now
				if (!stMatchSets[sFirstChar])
					stMatchSets[sFirstChar] = [];
				// if the match is a string
				stMatchSets[sFirstChar].push(row);
			}
		}
		// add the data items to the cache
		for (var k in stMatchSets) {
			// increase the cache size
			options.cacheLength++;
			// add to the cache
			addToCache(k, stMatchSets[k]);
		}
	}
	$input.keydown(function(e) {
				// track last key pressed
				lastKeyPressCode = e.keyCode;
				switch (e.keyCode) {
					case 38 : // up
						e.preventDefault();
						moveSelect(-1);
						break;
					case 40 : // down
						e.preventDefault();
						moveSelect(1);
						break;
                    case 8 : //backspace
                        options.control.backInput(e);
						openResults();
                        break;
					case 9 : // tab
					case 13 : // return
						if (selectCurrent()) {
							// make sure to blur off the current field
//							$input.get(0).blur();
//							e.preventDefault();
						}
						break;
					default :
						openResults();
						break;
				}
			}).focus(function(e) {
				// track whether the field has focus, we shouldn't process any
				// results if the field no longer has focus
                hasFocus = true;
				if (options.focusshow
					&& options.focusshow == "true") {
					openResults();
				}
			}).blur(function() {
				// track whether the field has focus
				hasFocus = false;
				hideResults();
				if (options.mustMatch) {
					var v = $input.val();
					if (v != input.lastSelected) {
						selectItem(null);
					}
				}
			})
//			.bind("input", function() {
//				// @hack:support for inputing chinese characters in firefox
//				onChange(0, true);
//			});
	hideResultsNow();
	function openResults() {
		active = -1;
		if (timeout)
			clearTimeout(timeout);
		timeout = setTimeout(function() {
			onChange();
		}, options.delay);
	}

	function onChange() {
		// ignore if the following keys are pressed: [del] [shift] [capslock]
		if (lastKeyPressCode == 46
				|| (lastKeyPressCode > 8 && lastKeyPressCode < 32))
			return $results.hide();
		var v = $input.val();
		if(v.length < 1){
			//判断如果为空值
			$input.removeClass(options.loadingClass);
			$results.hide();
		}
//		if (v == prev)
//			return;
		prev = v;
		if (v.length >= options.minChars) {
			$input.addClass(options.loadingClass);
			requestData(v);
		}
	};
	function moveSelect(step) {
		var lis = $("li", results);
		if (!lis)
			return;
		active += step;
		if (active < 0) {
			active = 0;
		} else if (active >= lis.size()) {
			active = lis.size() - 1;
		}
		lis.removeClass("ac_over");
		$(lis[active]).addClass("ac_over");
		// Weird behaviour in IE
		// if (lis[active] && lis[active].scrollIntoView) {
		// lis[active].scrollIntoView(false);
		// }
	};
	function selectCurrent() {
		var li = $("li.ac_over", results)[0];
		if (!li) {
			var $li = $("li", results);
			if (options.selectOnly) {
				if ($li.length == 1)
					li = $li[0];
			} else if (options.selectFirst) {
				li = $li[0];
			}
		}
		if (li) {
			selectItem(li);
			return true;
		} else {
			return false;
		}
	};
	function selectItem(li) {
		if (!li) {
//			li = document.createElement("li");
//			li.extra = [];
//			li.selectValue = "";
            if (options.control.getAttribute().check != "true") {
                $input.val("");
                options.control._result = new Object();
            }
			return;
		}
		
		var v = $.trim($("#text",li).text());
		input.lastSelected = v;
		prev = v;
		$results.html("");
//		$input.val(v);
		hideResultsNow();
		if (options.onItemSelect)
			setTimeout(function() {
				options.onItemSelect(li)
			}, 1);
	};
	// selects a portion of the input string
	function createSelection(start, end) {
		// get a reference to the input element
		var field = $input.get(0);
		if (field.createTextRange) {
			var selRange = field.createTextRange();
			selRange.collapse(true);
			selRange.moveStart("character", start);
			selRange.moveEnd("character", end);
			selRange.select();
		} else if (field.setSelectionRange) {
			field.setSelectionRange(start, end);
		} else {
			if (field.selectionStart) {
				field.selectionStart = start;
				field.selectionEnd = end;
			}
		}
		field.focus();
	};
	function showResults() {
		// get the position of the input field right now (in case the DOM is
		// shifted)
		var pos = findPos(input);
		// either use the specified width, or autocalculate based on form
		// element
		var iWidth = (options.width > 0) ? options.width : $input.width()+25;
		// reposition
		$results.css({
					width : parseInt(iWidth) + "px",
					top : (pos.y + input.offsetHeight) + "px",
					left : pos.x+1 + "px"
				}).show();
	};
	function hideResults() {
		if (timeout)
			clearTimeout(timeout);
		timeout = setTimeout(hideResultsNow, 200);
	};
	function hideResultsNow() {
		if (timeout)
			clearTimeout(timeout);
		$input.removeClass(options.loadingClass);
		if ($results.is(":visible")) {
			$results.hide();
		}
		
	};
	function receiveData(q, data) {
		if (data) {
			$input.removeClass(options.loadingClass);
			results.innerHTML = "";
			// if the field no longer has focus or if there are no matches, do
			// not display the drop down
			if (!hasFocus || data.length == 0)
				return hideResultsNow();
//			if ($.browser.msie) {
//				// we put a styled iframe behind the calendar so HTML SELECT
//				// elements don't show through
//				$results.append(document.createElement('iframe'));
//			}
			results.appendChild(dataToDom(data));
			showResults();
		} else {
			hideResultsNow();
		}
	};
	
	function dataToDom(data) {
		var ul = document.createElement("ul");
		var num = data.length;
		// limited results to a max number
		if ((options.maxItemsToShow > 0) && (options.maxItemsToShow < num))
			num = options.maxItemsToShow;
		for (var i = 0; i < num; i++) {
			var row = data[i];
			if (!row)
				continue;
			var li = document.createElement("li");
			
			if (options.formatItem) {
				li.innerHTML = options.formatItem(row, i, num);
				li.selectValue = row;
			} else {
				li.innerHTML = row[0];
				li.selectValue = row[0];
			}
			var extra = null;
			if (row.length > 1) {
				extra = [];
				for (var j = 1; j < row.length; j++) {
					extra[extra.length] = row[j];
				}
			}
			li.extra = extra;
			ul.appendChild(li);
			$(li).hover(function() {
						$("li", ul).removeClass("ac_over");
						$(this).addClass("ac_over");
						active = $("li", ul).indexOf($(this).get(0));
					}, function() {
						$(this).removeClass("ac_over");
					}).click(function(e) {
						e.preventDefault();
						e.stopPropagation();
						selectItem(this)
					});
		}
		return ul;
	};
	function requestData(q) {
		if (!options.matchCase)
			q = q.toLowerCase();
		var data =null;
        //使用cache
        if(typeof(options.control.getAttribute().usecache)=="undefined"||options.control.getAttribute().usecache=="true"){
            data=options.cacheLength ? loadFromCache(q) : null;
        }
		// recieve the cached data
		if (data) {
			receiveData(q, data);
			// if an AJAX url has been supplied, try loading the data now
		} else if (options.control.getDataSource()) {
			var data = loadData(q);
			options.control.triggerAttributeEvent("initdata", data);
            //使用cache
            if(typeof(options.control.getAttribute().usecache)=="undefined"||options.control.getAttribute().usecache=="true"){
                addToCache(q, data);
            }
			receiveData(q, data);
			// if there's been no data found, remove the loading class
		} else {
			$input.removeClass(options.loadingClass);
		}
	};
	
	function loadData(q) {
        var data  = new Array();
        var control = options.control;
        //认证输入是否合法
        var flag = control.validateControl(q);
        if (!flag) return;
        var oDS = control.getDataSource();
        if (oDS) {
        	control.triggerAttributeEvent("beforequery");
            var oParam = control.getParam();
            var queryTag = control.getAttribute().querytag;
            //如果是复选，则转换输入内容
            if (control.getAttribute().check == "true") {
                q = control.formatCheckInput(q);
                if (q == "") return;
            }
            var oRequest = new Object();
            oRequest.rowcount = true;
            oRequest.params = {};
            for (var i in oParam) {
            	oRequest.params[i] = oParam[i];
            }
            oRequest.params[queryTag] = q;
            oRequest.start = 0;
            if(typeof(control.getAttribute().autocompleterownum)!="undefined"){
                oRequest.rownum = control.getAttribute().autocompleterownum;
            }else{
                oRequest.rownum = 10;
            }

            if (control.getAttribute().type == "code") {
            	if (q.trim() == "") return;
                oRequest.type = control.getAttribute().coderes;
                //编码查询不需要参数
                delete oRequest.params.child;
                delete oRequest.params.pid;
            }
            var oResult = oDS.queryData(oRequest);
            data = oResult.records;
        }
		return data;
	};

	function loadFromCache(q) {
		if (!q)
			return null;
		if (cache.data[q]){
            return cache.data[q];
        }

		if (options.matchSubset) {
			for (var i = q.length - 1; i >= options.minChars; i--) {
				var qs = q.substr(0, i);
				var c = cache.data[qs];
				if (c) {
					var csub = [];
					for (var j = 0; j < c.length; j++) {
						var x = c[j];
						var x0 = x.cn;
						if (matchSubset(x0, q)) {
							csub[csub.length] = x;
						}
					}
					return csub;
				}
			}
		}
		return null;
	};
	function matchSubset(s, sub) {
		if (!options.matchCase)
			s = s.toLowerCase();
		var i = s.indexOf(sub);
		if (i == -1)
			return false;
		return i == 0 || options.matchContains;
	};
	this.flushCache = function() {
		flushCache();
	};
	this.setExtraParams = function(p) {
		options.extraParams = p;
	};
	this.findValue = function() {
		var q = $input.val();
		if (!options.matchCase)
			q = q.toLowerCase();
		var data = options.cacheLength ? loadFromCache(q) : null;
		if (data) {
			findValueCallback(q, data);
		} else if (typeof option.dataControl == "object") {
//			$.get(makeUrl(q), function(data) {
//						data = parseData(data)
//						addToCache(q, data);
//						findValueCallback(q, data);
//					});
		} else {
			// no matches
			findValueCallback(q, null);
		}
	}
	function findValueCallback(q, data) {
		if (data)
			$input.removeClass(options.loadingClass);
		var num = (data) ? data.length : 0;
		var li = null;
		for (var i = 0; i < num; i++) {
			var row = data[i];
			if (row[0].toLowerCase() == q.toLowerCase()) {
				li = document.createElement("li");
				if (options.formatItem) {
					li.innerHTML = options.formatItem(row, i, num);
					li.selectValue = row[0];
				} else {
					li.innerHTML = row[0];
					li.selectValue = row[0];
				}
				var extra = null;
				if (row.length > 1) {
					extra = [];
					for (var j = 1; j < row.length; j++) {
						extra[extra.length] = row[j];
					}
				}
				li.extra = extra;
			}
		}
		if (options.onFindValue)
			setTimeout(function() {
						options.onFindValue(li)
					}, 1);
	}
	function addToCache(q, data) {
		if (!data || !q || !options.cacheLength)
			return;
		if (!cache.length || cache.length > options.cacheLength) {
			flushCache();
			cache.length++;
		} else if (!cache[q]) {
			cache.length++;
		}
		cache.data[q] = data;
	};
	function findPos(obj) {
		var curleft = obj.offsetLeft || 0;
		var curtop = obj.offsetTop || 0;
		while (obj = obj.offsetParent) {
			curleft += obj.offsetLeft
			curtop += obj.offsetTop
		}
		return {
			x : curleft,
			y : curtop
		};
	}
}
jQuery.fn.autocomplete = function(options, data) {
	// Make sure options exists
	options = options || {};
	// set some bulk local data
	options.data = ((typeof data == "object") && (data.constructor == Array))
			? data
			: null;
	// Set default values for required options
	options.inputClass = options.inputClass || "ac_input";
	options.resultsClass = options.resultsClass || "ac_results";
	options.minChars = options.minChars || 1;
	options.delay = options.delay || 500;
	options.matchCase = options.matchCase || 0;
	options.matchContains = options.matchContains || 0;
	options.cacheLength = options.cacheLength || 1;
	options.extraParams = options.extraParams || {};
	options.loadingClass = options.loadingClass || "ac_loading";
	options.selectFirst = options.selectFirst || true;
	options.selectOnly = options.selectOnly || false;
	options.maxItemsToShow = options.maxItemsToShow || 10;
	options.width = parseInt(options.width, 10) || 0;
	
	this.each(function() {
				var input = this;
				new jQuery.autocomplete(input, options);
			});
	// Don't break the chain
	return this;
}
jQuery.fn.autocompleteArray = function(data, options) {
	return this.autocomplete(null, options, data);
}
jQuery.fn.indexOf = function(e) {
	for (var i = 0; i < this.length; i++) {
		if (this[i] == e)
			return i;
	}
	return -1;
};
